CWNA-109

CWNA-109 practice questions, page 3 of 5, with answer review and explanations.

Question 11

When using a spectrum analyzer to look for non-Wi-Fi interference sources, you notice significant interference across the entire 2.4 GHz band (not on a few select frequencies) within the desktop area of a user's workspace, but the interference disappears quickly after just 2 meters. What is the most likely cause of this interference?

  1. USB 3 devices in the user's work area
  2. Excess RF energy from a nearby AP
  3. Unintentional radiation from the PC power supply
  4. Bluetooth devices in the user's work area

Question 12

You recently purchased four laptops containing dual-band 802.11ac adapters. The laptops can connect to your 2.4 GHz network, but they cannot connect to the 5 GHz network. The laptops do not show the 5 GHz SSIDs, which are different than the 2.4 GHz SSIDs. Existing devices can connect to the 5 GHz SSIDs with no difficulty. What is the likely problem?

  1. Faulty drivers
  2. Interference from other WLANs
  3. DoS attack
  4. Interference from non-Wi-Fi sources

Question 13

Return Loss is the decrease of forward energy in a system when some of the power is being reflected back toward the transmitter. What will cause high return loss in an RF transmission system, including the radio, cables, connectors and antenna?

  1. The use of 50 ohm cables longer than one meter in the RF system
  2. A significant impedance mismatch between components in the RF system
  3. High output power at the transmitter and use of a low-gain antenna
  4. A Voltage Standing Wave Ratio (VSWR) of 1:1

Question 14

The IEEE 802.11 standard requires VHT capable devices to be backward compatible with devices using which other 802.11 physical layer specification (PHY)?

  1. ERP-PBCC
  2. DSSS
  3. OFDM
  4. HR/DSSS

Question 15

In which plane of the three commonly defined networking planes is an access point configured by a WLAN controller?

  1. Administrative
  2. Management
  3. Security
  4. Data